Filming the unfilmable - almost

Perhaps the only books that might defeat the screenwriter and director are completely static works.

Stand by, in the coming months, for a slew of filmed versions of books generally regarded as unfilmable.

Already out is On the Road, from Jack Kerouac's novel written in a single three-week burst in April 1951.

Its picaresque story of Sal Paradise, Dean Moriarty and their beat-generation pals is full of incident, but - as critics have pointed out - their lives hardly amount to a plot and their road is directionless.

Francis Ford Coppola bought the film rights in 1980 but had to wait 30 years to find the right director in Walter (The Motorcycle Diaries) Salles.

In its dusty wake is another fictional journey, Ang Lee's Life of Pi.

Adapted from Yann Martel's Booker-winning novel, it tells how an Indian boy, Piscine Patel, survives a shipwreck that kills his family, and survives for 227 days in a small lifeboat with only a Bengal tiger, a hyena, a zebra and an orang-utan for company. The Canadian Maclean's magazine described it as "a head-scratching combination of dense religious allegory, zoological lore and enthralling adventure story".

Then comes Cloud Atlas, from David Mitchell's stunning 2004 novel in which six stories of human predation are folded inside each other.

Each comes to an abrupt halt before shifting to the next, concluding after a lengthy middle sequence set in a post-apocalyptic future.

The movie (by the Wachowski brothers) simplifies the complex structure into a series of "Didn't we meet in a previous life?" encounters, but looks fantastic.

So does this mean there is no such concept as "unfilmable" any more?

It depends on your concept of form: Michael Winterbottom took Laurence Sterne's Tristram Shandy - a spoof biography with so many windy digressions that the "hero" hardly gets to live at all - and made an 18th-century romp with Steve Coogan and Rob Brydon.

Joe Wright elected to film the 800-page Anna Karenina by scaling it down so the action took place in a theatre: he simply took an epic and made it a mini-epic. An elaborate prose style is no bar to filming: see A Clockwork Orange, Lolita, Last Exit to Brooklyn, even Ulysses.

Perhaps the only books that might defeat the screenwriter and director are completely static works: Pilcrow by Adam Mars-Jones, say, in which an arthritic narrator minutely describes all he can see from his bed and myriad details from his boyhood.

Or Being Dead by Jim Crace, in which a murdered couple lie undiscovered for days and we read in detail about their physical decomposition. Try selling that to arthouse titan Harvey Weinstein.